1. Technical Field
The present invention relates to a light source device and a projector equipped with the light source device.
2. Related Art
In the past, there has been known a projector, which modulates light emitted from a light source device in accordance with image information, and then projects the light. In such a projector, there has been used a discharge light source device as the light source device in the past. However, in recent years, the chance of using a light emitting device such as a light emitting diode (LED) or a semiconductor laser has increased. Further, there has been used a light source device for performing wavelength conversion on the light from the semiconductor laser or the like using a fluorescent material.
JP-A-2005-277331 (Document 1) discloses a light emitting device provided with a light transmissive member including a fluorescent material and a reflecting member as a reflecting surface in order to improve the efficiency of the light (fluorescence) on which the wavelength conversion has been performed.
However, in the light emitting device (a light source device) of Document 1, the light, which has been emitted from the fluorescent material and has reached the side surface of the light transmissive member, is reflected by the reflecting surface toward the inside of the light transmissive member. However, an experiment having been conducted by the inventors shows the fact that although a part of the light having returned to the inside of the light transmissive member is emitted from an upper surface of the light transmissive member, the remaining component thereof is confined in the inside of the light transmissive member, and fails to be used as the light for illumination. Therefore, sufficient improvement effect in the efficiency of the fluorescence is not obtained.
Therefore, there have been demanded a light source device capable of improving the efficiency of the fluorescence and a projector equipped with the light source.